Stereoscopic motion-picture film marking apparatus



R. ORIOL .Fuy 25, 195@ 2 Sheets-Sheet l Original Filed Oct. 50, 1941 .uy 25, 195@ R. ORIOL 2,516,75

STEREOSCOPC MOTION-PICTURE FILM MARKING APPARATUS Original Filed Oct. 50, 1941 2 Sheets-Sheet 2 E D U E 2 59 6 :s 2 /P E :Q E 59 D /U i9. 46 e l l l as M o 'M Hrm/@wey Patented .uly 25, 1950 STER-EOSCO-PIC MOTION-PICTURE FILM MARKING APPARATUS Ramon Oriol, Manila, P. I.; vested in the Attorney General of the United States Original application October 30, 1941, Serial No.

417,194, now Patent No. 2,365,212, dated December 19, 1944.

Divided and this application 3 Claims.

My invention relates to an apparatus for the making and projecting of stereoscopic motion pictures.

An important object of my invention is the provision of an apparatus for making stereoscopic motion picture nlm which may be rapidly operated and substantially automatically controlled as well as apparatus for projecting the stereoseopic film onto a viewing screen, which rst apparatus includes a unique means for treating the iilm'with rays of light in such a manner that a light sensitive means comprising a part of the second apparatus may synchronizethe lm with a viewing apparatus Worn by a spectator in such a manner that the said spectator will see the pictures stereoscopically.

The principle involved in the making of stereoscopic motion pictures is substantially the same as the principle involved in the making of the familiar still stereoscopic pictures. Every other frame 'of the nlm is exposed to a ray of light entering a right opening in the shutter of the camera and the other frames of the film are exposed to a ray of light entering a left opening of the shutter. The pictures taken through the right shutter opening Will be visualized by the right eye of the spectator and the pictures taken through the left shutter opening will be visualized by the left eye of the spectator. The mechan ical apparatus worn by the spectator during the showing of the picture is uniquely synchronized with the nlm in such a manner that the vision of the left eye will be obscured when the rig-ht eye pictures are projected and whereby the vision of the right eye will be obscured when the left eye pictures are projected. By running the nlm at an essentially fast rate of speed and by synchronizing the viewing apparatus with the film in a manner whereby the right eye will observe only the pictures taken from the right side of the camera and the left eye will observe only the pictures taken from the left side of the camera, a bifocal picture of the object photographed is obtained and an illusion of depth is created.

Another object of my invention is the provision of an apparatus of the above-mentioned character that is simple in its construction and elicient and efficacious in operation.

Other objects and advantages of my invention will be apparent during the course of the following description.

In the drawings, forming a part of this specilication, and wherein like numerals are employed to designate like parts throughout the same:

Figure 1 is a perspective diagrammatical view of a camera embodying my invention,

Figure 2 is a fragmentary plan view of a stereoscopic film taken by the camera apparatus illustrated in Figure 1,

Figure 3 is a fragmentary perspective view of a modification of the film illustrated in Figure 2,

Figure 4 is a fragmentary plan view of a further modification of the film,

Figure 5 is a plan view illustrating the relative size and shape of the picture projected by the film illustrated in Figure 2,

Figure 6 is a plan view illustrating the relative size and shape 0f a picture projected by the nlm illustrated in Figure 3,

Figure '7 is a plan view illustrating the relative size and shape of a picture as projected by the nlm illustrated in Figure 4,

Figure 8 is a diagrammatical view of a picture projection apparatus embodying my invention and illustrating a viewing instrument associated therewith through which a spectator may view the projected pictures stereoscopically, means being shown to synchronize the viewing apparatus with the film as it is run through the projector, and I Figure 9 is a perspective View illustrating a modification of the camera illustrated in Figure 1.

Attention is rst directed to Figure 1, which illustrates my improved camera construction. It is to be understood that only such portions of the camera are here shown as is necessary to illustrate the instant invention.

In the accompanying drawings, wherein for the purpose of illustration, is shown a preferred embodiment of my invention, the numeral l0 designates a shield adapted to be fixedly mounted at the front of the camera. The shield is of essentially elongated formation and the substantially rectangular apertures Il and l2 provided at the opposite ends thereof are alternately opened and closed by the shutter disk I3 mounted for rotation relative to the shield. The shield and shutter are disposed in a light-tight housing and light is admitted into the housing through the apertures II and I2 by action of the shutter I3. The shutter may be rotated in any desired manner and it is formed at spaced intervals with windows or apertures I4 which register with the apertures II and I2 in the shield. The shutter apertures I4 are arranged in such relation with each other that only one of the shutter apertures will register with the shield apertures at any one time and so that the shield apertures will be alternately opened and closed. Thus, if the shield aperture II is open by reasonof the fact that a shutter aperture I4 has moved into register therewith, the other shield aperture I2 will be closed by reason of the fact that an impervious portion of the shutter disk is disposed in .register `there-- with. I prefer that the apertures I4 be uniquely related so that the open shield' aperture will be entirely closed before another shutter aperture begins to open the closed shield aperture. As soon as the shutter disk has rotated a distance sun'icient to entirely close the aperture kI I, the aperture I2 is being opened by movementof another shutter aperture into register therewith. It is to be understood that in the taking .of motion pictures the shutter `will revolve at an essentially high rate. ofspeed andthat the Opening and closing of the shield apertures will be substantially instantaneous. Also the shutter actuator mechanism is synchronized with the nlm actuator lmechanism in the conventional manner whereby an unexposed frame of vthe nlm strip will move into position for each opening of the Shield apertures.

The light entering thecamera through the apertures II and I2 must pass through v'the focusing lens I5 armi impinge against the nlm strip I6. The lens 4and nlm are located on the longitudinal center of the camera and theapertures II and I2 are disposed at opposite sides thereof. It is, -thereforanecessary to provide some ,means for reflecting the rays of .light entering the apertures II and I2 so vthat they will be directed along Atheilongitudinal centerline of the camera, along the principal axis of the lens and centrally impinge against `the registering -frame .of `the nlm strip, here illustrated as being the frame I'I. To accomplish this purpose, Ihave interposed the prisms I8, I9 and 20 between the shield and shutter mechanism and the lens I5.

The prism I8, of essentially triangular formation in plan, is disposed directly rearwardly of `the shield aperture II and thebase 2I thereof is arranged at the outside, whereby rays of light entering the camera through the aperture II will .be reflected inwardly toward the vlongitudinal center of the camera and into the prism I9. The last mentioned prism is of essentially square formation in plan and is located on the longitudinal center of the camera. Similarly, the prism 20, of triangular formation in plan, is

located directly ybehind the shield aperture I2 and the base 22 thereof .is arranged at the out side to renect rays of light entering the camera ,through the aperture I2 toward the longitudinal `center of the camera and into the intermediate prism I9.

A prism I9 is nxedlymounted within the camera and comprises'a plurality of prism elements 23, 24, y2 5 and 26. -Each o f 4the prism elements is of right-.triangular formation in plan and has the apex thereof disposed atthe center of the prism I9 whereby light entering prism I9 from the prism I8 will normally enter the 'hase of -the prism element 24 and be retracted through the base of .Prism velement 2.3; and. .simlarlv. .light `1eiie,1 i

`segmental gears 29 and 3i). A focusing knob 3| is mounted on the shaft 32 which extends transversely through the camera and is suitably mounted for rotation relative thereto. A right hand worm .gear 33 is formed on the shaft 32 to mesh with the segmental gear 30 and a left vhand worm gear 34 is formed on the shaft 32 -to mesh with the segmental gear 29. The lens I5 is formed with an L-shaped supporting member 35, the arm 36 of which extends in the direction of the prisms and below the shaft 32 and is suitably mounted for sliding movement within the camera. The upper surface of the portion of the arm 36 extending below the shaft is provided with a plurality of transverse teeth members 317 which .mesh vwith Ythe teeth of ,the l.spur gear 38 n-xedly carriedby the shaft.

It may be thus seen that rotation of the shaft .32 .by means ,of the focusing knob 3| `will rock the prisms I8 and 26 about theaxes of their support-` ing shanks 2l and 28 and that the lens .I5 will be moved toward yor away from the nlm I6. The action of the lens I5 and prisms I8 and 20 is therefore synchronized to permit the prisms .to automatically adjust themselves tothe object being photographed when the lens is moved to bring the object into focus on the nlm I 6.

A segmental plate 39 is .mounted .in proximity tothe focusing knob 3| andthe numerals 4B inscribed on .the outer face'thereof cooperate with the index pointer 4I carried 7'by the knob to indicate the focused position'ofv the lens. As vthe focusing knob is rotatedin a clockwise direction to .focus the lens upon an objectfdisposed closer to the camera, the spur gear 38 in mesh with the teeth 3l will move the lens in a direction away from the nlm and the worm .gears 33 and 34 will rock the prisms ,2B and I8 to .permit thesame to properly reflect the said-object.

propose that the Viewing instrument used in ,connection with the projection of the nlm be operated by a light sensitive means .and `that the light sensitive means .be energized by light passing through the nlm being projected. Itis there.-

. fore necessary to provide some means for controlling the passage of light through the nlm and I proposeto accomplish this end by over-exposing one :marginal edge of each frame of the nlm whereby, afterdevelopment of the nlm, the overexposed marginal edge thereof will be opaque to prevent light rays from passing therethrough and the opposite marginal edge will be transparent to permit light rays to readily pass therethrough.

I have provided a pair of spaced substantially light-tight housings 42 and 43 of essentially triangular formation in plan. The housings are mounted within the camera at opposite sides A of the Vfilm track and the inner walls 44 and y45 thereof are disposed in spaced parallel relation. The apexesof the housings are open and extend in the direction of the film whereby the openings will be disposed in confronting relation with the sensitized surface of the nlm. I prefer that fthe nlm confronting lends of the khousings be located lattheouter side of the sprocket tracksill whereby' light from within the housings will be removedy a maximum distance from the portion of the frame disposed between the tracks 46, which last portion is adapted to be exposed to the rays of light entering through the shield apertures II and I2.

A lamp 4l is mounted within each of the housings 42 and 43, which lampsare' adapted to be separately illuminated by i an electric control means carried by .the shutter I3. Thus, each of if,

the lamps will be separately illuminated simultaneously with the opening of arespective one of the apertures il and I2 in the shield. As here illustrated, the lamp in housing 42 will be illuminated simultaneously with the opening of shield aperture II and the lamp'in housing 43 will be illuminated simultaneously with the opening of shield aperture I2.

A metallic hub 48 is carried by the shutter disk I3 for rotation therewith. Theperiphery of the hub is provided with a plurality of non-electrical conducting inserts 4Q, one insert being provided for each of the shutter apertures I4. A brush 50, mounted in proximity to the hub is at all times engaged with the metallic portion thereof and brushes 5I and 52 mounted at opposite sides of the hub alternately engage with the metallic portions of the hub and with the non-conducting inserts 49. As clearly illustrated in the drawings, the inserts have substantially greater surface area than the portion of the hub interposed therebetween and their relation is such that one of the brushes 5I or 52 will at all times be engaged with an insert during the interval when the other of the brushes is engaging the metallic portion of the hub. The numeral 53 designates an electrical conductor leading from the positive side of a source or current supply and connecting with the brush 5u whereby to at all times supply current to the metallic hub 43. A conductor 54 'connects the brush 5I with one terminal of the lamp mounted in housing 42 and a conductor 55 connects the brush 52 with one terminal of the lamp mounted within the housing 43. The conductor 56 connects the other terminal of each of the lamps with each other and a conductor 5l connects with the conductor 5E at the point 58 and extends therefrom to the negative side of the source of current supply.

When the aperture II in the shield is opened f -factrthat the brush to which kit is connected is in engagement with one of the non-conducting inserts 49.

Thus, when aperture II is open, the lamp mounted in housing 42 will be illuminated to overexpose the confronting marginal edge of the picture frame Il. When aperture II is open the light will enter the camera from the left of the principal axis oi the lens and frame Il is therefore designated as a left eye view picture.

Continued rotation of the shutter I3 will close shield aperture II and open shield aperture I2. Simultaneously with the opening of shield aperture I2 the ',lm actuating mechanism will move the adjacent frame 59 of the lm strip into register with the openings in the ends of the housings 42 and 43. Brush 5I will then be in engagement with one of the non-conducting in- 'serts 49 and brush 52 will be in engagement with the metallic hub 48. The rays of light will enter the aperture I2 from a point at the right of the principal axis of the lens I5 and the frame 59 of the iilm strip is therefore designated as a right eye View picture. Current will now iiow along conductor 53 to brush 50, through hub 48 to brush 52 and along conductor 55 to the lamp in housing 43. From the lamp the current may flow along conductors 56 and 51 to the power source. The lamp in the housing at the right side of the film strip will therefore be illuminated to overexpose the right marginal edge of frame 59.

It may thus be seen that the shield apertures I I and I2 will be alternately opened and that the lamps contained by housings 42 and 43 will be alternately illuminated in synchronism therewith. Therefore alternate right and left eye view pictures will be projected on to the adjacent frames of the film strip and as hereinabove pointed out, all of the left eye View pictures will have an opaque left marginal edge and a transparent right marginal edge while all of the right eye view pictures will have an opaque right marginal edge and a transparent left marginal edge.

In Figure 9 I illustrate a modification of the arrangement of the refracting prisms I8, I9 and 20. In this form of the invention, the end prisms I8 and 2E are iixedly mounted within the camera and the prism I3 is mounted for rotation therebetween. The film strip I5 extends over a roller G0 in the conventional manner, and the roller is provided with sprocket teeth 5I which enter the sprocket tracks 46 of the iilm strip to effect movement of the iilm within the camera. A spider 52 is carried by the roller shaft S3 and is adapted to be rotated through an angle of each time it is necessary to move the film. The above means for moving the film is conventional in the art and no further explanation is therey fore thought to be necessary.

I desire that the prism I9 be rotated in direct ratio with the film roller 5t and I have therefore provided a train of gears which includes a beveled gear 64 carried by the roller shaft, which gear meshes with a beveled gear 65 xedly mounted on one end of an idler shaft B5. The opposite end of the idler shaft 58 extends in the direction of the prisms and carries a beveled gear 6l which meshes with the beveled gear 68 mounted on one end. of a second idler shaft 69. The shaft 52 extends at right angles to the idler shaft G5 and in the direction of the shank 'l0 depending centrally from the prism Iii, whereby the beveled gear ll carried by the opposite end of the idler shaft 69 will mesh with a beveled gear l2 carried by the shank. The beveled gear 64 is of the same diameter as the beveled gear 65, the beveled gear 6l is oi the same diameter as the gear G3 and beveled gear il is of the same diameter as beveled gear l2 so that a rotation of the roller 60 through 90 will rotate the prism I9 through 90.

Prism I9 is here illustrated as comprising triangular prism elernents I3 and "I4, having the 'thereof joined together and coated with silver or other reflective material. The composite prism I9 is therefore of square formation in plan .and is diagonally bisected by the bases of the prism elements, Obviously, this construction will Ipermit the reiiective material coatinguthe Qaa-sesofltheprism elements to-reflect raysof light @normally enteringcne side of either ofthe prism -elements `normally through the other sideofthe element.

If desired,-the prismsi and 20 may be rocked vabout a vertical axis :inthe manner `described Vfor thefirstiforlnofl-the invention and light rays similarly enterV prisms I8 andl 20 through laterally `spaced shield apertures lin ythe manner hereinabove described. Thus, vif 'the prisms are asso- -ciated-with-/the camera mechanism illustrated in Figu-re -1, light rays entering prism i8 through `shield aperture ll will Ybe deflected into prism elements klgof prism I9. The lightrays willbe rreflected fromgthe reflective material coating the base of Iprism element along -the vprincipal axis of lens andby *meansfor the-lens'it willbe 4focused on'the registeringframe-fof the fil-m strip v'1 6. When -therollert is rotated through an "angle of-90^to move another fra-me ofthe nlm strip into register with the lens l5, the `prism Al!! will al-so be rotated through an-angle of 90 and -shielcl laperture l2 will be opened teperrnit light iays-toenter the prism 20. The rotation of prism 1'9 will lnow permit-the light raysreflected from prism l-213 to Abe directed from prism clement 7d alongthe principal axis of the lens i5 and focused onthe righteye view'fra-me 59 inregisterftherewith.

If the film thus produced is run through a :pictureprojection apparatus, the right and left :eye viewpictures Aof the film will be alternately vprojectedon to a viewing screen. Figure `itil- "lustrates theparts-of a picture projection appa* ratus lwhich are Inecessary -to illustrate the apjplication of the present invention. A lamp l5 and 'a 'condenser lens *TG are mounted rearwardly 101 the `film stripl in the conventional manner anda-focusing lens il is mounted in front of the `jfilm strip to 'properly project the yrays of light lrliassingfthrough the stri-ponto `a suitable viewing screen. Electrical energy is supplied to the lamp iby means of an electric circuit 1.8, w'hichrcircuit 'includes a 'conductor 79 leading -frorn the .positive side of the source of the current supply 'tojone terminal `of the lamp and a conductor B (which connects with the Iot-hertermina1of the lamp'andextends to 'thenegatve side ofthe cur `'rentsource -`'Il'iejdrawing here-illustrates one of .rtheiram'es 59 as being in register with the lensof 'theI projection apparatus whereby illuminationl of fthe'lamp V'l5 will cause a-right eye View picture to be projected 'onto the-viewing screen.

Shields "8| and I82 are arranged in iront of the strip rlGand atyopposite sides thereof. The shields extend from the sprocket tracks 46 to `a Apoint -forwardly and laterally 'of the vfilm @whereby to shield the light sensitive members83 kandj'il from therays of light passing through-'the illm positive. The light sensitive Vmembers preferably "comprise photo-electric `cells and vthese 'members are'individually excited or energized by `rays of light passing through the transparent marginal edge ofthe partcularframe in register .with v.the lens 'of the gprojector. It will A'be re- A*memberedin this Vconnection that-but one ofthe marginal edges of each frame is transparent and it Will'therefore be readily understood that but one ofthe light sensitive members will be energized by any: one particular lframe. It will also `be remembered that the opposite marginal edges :oi-adiacentframes are transparent whereby the llight sensitive lmembers will -be 'alternately excited as "the flm is vcaused to runthrough the projector. Other shields 185Land'86 are arranged between the light sensitivemembersand thelamp -15 in such relation as Atoprevent light raysfrom Ltheflamp firom .having direct access to :the :mem-

bers .83.and B4. This unique arrangement, there- `fore, makes it .necessary ,that any rays having access to the members vB3 and `8l! must. pass through :the marginal edges of .the iilm'strip.

In orderthat a spectator may view the pictures .proj ected. upon the viewing screenstereoscopically it is .necessary that he see the right eye view pictures l5! with his righteye only and .that fhe `see the left eyeviewpictures .ll with hislefteye only. .I .have therefore provided .a viewing instrument-.tl which may be worn by the spectator and which includesa vmovableshutter elementBB adapted to operate in synchronismwith the pictureprojection apparatus and to .alternately obstruct the vision of one eye while alternately permitting. a clear viewof'the other eye.

The viewing ,instrument :comprises an essentially Vrectangular supporting mask 89 vwhich is adapted to cover the Y.eyes of vthe Aspectator .and which may be detachably applied in thisposition .byzmeans ofthe temple bars .9.0. Theshutterelement 238 centrally mounted on the supporting Vmask by .means of the .pivot pin .9| is provided with .oppositely extending arms .92 and-93 which cover .the slits 9.4 and 95, respectively, in the 'mask As .clearly illustrated in the drawing, the

slit 94 isadapted to register with the right eyeof .the spectator and the slit '95 is adaptedto .register with .theLleft eye o'ffthe` spectator. Arnetallic yarm 'JSS ixedly mounted on Vthe shutter, extends :between a pair `of electro-magnets 9.1 .and :98 by which it vis alternately attracted -to `oscillate the shutter about the pivot 9| whereby :to alternately .open and close the slits .Stand 95.

Inorclerthat the viewing .instrument will op .erateiin Asynchronisn'l with .the picture projection .apparatus' have connected the electro-magnets .ill and '98 .in the .electric circuit L18 and, in .order rthatthelig-ht sensitivemembers 83 anddmay control the electrical impulses transmitted Ato the electro-magnets, .I have also connected A.these members in the circuit. `The energy developed by the conventional photo-electric. celll isnot suf- .ciently strong to operate theelectromagnets 191 and and Ihave therefore provideda photoelectric relay switch S9 which `is operated 'by .the .photo-electric vcells and which in turn permits current `Vfrom .fthe electric circuit to flow through rthe electromagnets. Gonductors .-100 and IUI con- `nectthef'relay switch a99 withthe electric circuit .1118, conductors i532 and '103 connect the .photoelectric cell 184 tothe vrelay switch and conductors .i 04 and 'l 05 connect the 'photo-electric cell .183' to the-relay switch. One terminal of the electroinagnet 9.1 is connected to the correspondingzteryminal of electro-magnet y98 by the conductor 106 .and this v.conductor is connected .to the relay `switrzhfbymeans .of theconductor 4.01. 'The `other terminal of electro-*magnet 91 v4isconnectedfto the relay switch ybya conductor Hi8 and the other terminal of electro-magnet 98 is connected to fthere'lay switch by conductor '1.89.

As 'the-alternate right and left eye viewpictures '59 and Il'l of the i'llm stripare projecte'dontofthe rviewing screen, the opposite transparent marginal edges ofthe picture frames will `permit the photo- Velectric cells 83-an-dl84to be alternately excited.

When a right .eye View picture 59 is in .register with the 'projector lenses, the 4transparent `marginal edge thereof Vwill ypermit 'light rays *from vlampto affectQthe-photo-electric cell83 which will in turnfoperate the relay switch t9 tofrper- 59 mitl current from the electric circuit 'I8 `to flow through the electro-magnet Sil.V When the electro-magnet 98 is thus energized, it will attract the arm 9B of the shutter element 88 and rock. the same about its pivot to open the righ* eye slit 94 and to close the left eye slit d5. Thus, during the showing of the picture frame 59, the Vision of the left eye of the spectator will be obstructed while the right eye of the spectator will be permitted to clearly obse-rve the picture. Con-- versely, when a left eye view picture l'l is in register with the projector lenses= the opaque marginal edge thereof will prevent light rays from the lamp 15 from having access to the photo electric cell 83 and the transparent marginal edge thereof will permit light rays from the lamp to have access to the photo-electric cell 84. In this instance, the photo-electric cell 8d will operate the relay switch 9S to permit current from the circuit 'ifi to flow through the electro-magnet Bl, whereby the arm 95 of the shutter elements will move in the direction of the electromagnet 91 to rock the shutter element about its pivot. In this position of the shutter the slit 94 will be covered and the slit 95 will be opened whereby the vision of the right eye of the observer will be obstructed while the left eye will be perm mitted to clearly observe the projected picture.

The stereoscopic lm must be run through the projecting apparatus at substantially twice the speed of ordinary lm if flickering of the pictures is to be prevented. The above, of course, is true only if the individual frames of the lm are of the same size and shape as the conventional or ordinary frames. In Figure 2, I illustrate a nlm which depicts a stereoscopic nlm having picture frames of a size similar tc the frames of con'- ventional or ordinary film. It is customary to run lm having frames of this size through the projector at approximately sixteen frames per second. It will therefore be necessary that the stereoscopic lm having frames of this size be run at approximately thirty-two frames per Second. If the depth of each frame is reduced to approximately seventy-five percent of the depth of the conventional frame, in the manner illustrated in Figure 3, the lm be run approximately twenty-four frames per second. I prefer, however, that the nlm to be used in my stereoscopic projector apparatus be provided with frames of approximately one-half the depth of the frames of the conventional nlm. Such a film is illustrated in Figure i and this film may be run through the projector at the conventional rate of sixteen frames per second. Modern ino-j tion picture nlm may be greatly enlarged in the projection thereof and, if the frames of the type illustrated in Figure 4 are enlarged several times more than is necessary in the projection of the conventional film, the result will be a projected picture having a relative size and shape substan tially as illustrated in Figure 7.

Figure 5 illustrates the relative size and shape of the picture projected from the conventional film, Figure 6 illustrates the relative size and shape of a picture projected from the slightly reduced frames illustrated in Figure :2 Figure l illustrates the relative size and shape of a picture projected from the ilm illustrated in Figu ure 4. The advantage of using the reduced frames, as illustrated in Figure fr, is that the speed at which the nlm is run through the projector will be standard, thus permitting standard sound tracks to be printed thereon.

It is to be understood that any number of viewing'instruments 81 may be used and that the invention is capable of being used in a motion picture house having a relatively large attendance. An inniteI number of viewing instruments may be attached in the circuits leading from the relay switch to the electromagnets and all of the instruments would then bel controlled by the impulses transmitted to the relay switch by the light sensitive cells 83 and 84.

I prefer that a permanent mask be applied to the camera when the pictures are taken, which mask will produce a fading shadow HG at each side of the film frames, whereby the sharp edges of the frame pictures will merge into the viewing screen in the projection of the nlm. When viewing a stereoscopic picture the horizontal edges of the'picture frames v,will always coincide optically; however, the side edges of the adjacent frames may not be in perfect alignment. The result is that the spectator is subjected to considerable eye strain which may be very inconvenient and annoying. If, however, the side edges of the .frames are faded in the manner illustrated, this undesireable condition is obviated.

This application is a division of the application of Ramon Oriol, Serial No. 417,194, filed October 30, 1941, for stereoscopic Motion Picture Device, now matured into Letters Patent No. 2,365,212, issued December 19, 1944.

Having thus described my invention, I claim:

1. In a camera of the type adapted to carry a photographic film, means for imparting a step by step motion to the nlm, means for admitting rays of light onto the intermediate portion of the nlm alternately from spaced points located at opposite sides of the said film, housings arranged at opposite sides of the each or said housings having a restricted aperture opening against a respective marginal edge of the nlm', lamp means disposed within each of said housings, and means for alternately illuminating the said lamp means in synchronism with said light ray admitting means whereby the opposite marginal edges of adjacent film sections will be overexposed and rendered opaque.

In a photographic device having provision for moving a strip of film therethrough, the comhination of a shield having right and left apertures; a shutter mounted for rotation on the said shield, said shutter having apertures movable into register with the right and left shield apertures in a manner to alternately open the same; a housing disposed in front and at each side of the film, each of said housings having an aperture opening against a respective marginal edge of the nlm; lamp means disposed in each of the said housings; and controller means carried by the shutter and electrically connected to the lamps, said controller means being operative to alternately illuminate the lamps simultaneously with the alternate openings of the said shield apertures.

3. In a photographic device having provision for moving a strip of iilm therethrough, the combination of a shield having right and left openings; shutter means for alternately uncovering the shield openings; a housing disposed in front and at each side of the nlm, each of said housings having an aperture opening against a respective marginal edge of the nlm; lamp means disposed in each of said housings; and controller means carried by the shutter and electrically connecting with the said lamps, said controller means being operative to illuminate a respective one of the lamps when the left shield opening is uncovered-'2 and to; illuminate the: other: of; thef lamps whenl the right` sheldi opening; is,1 uncovered..

RIAMGNf ORIOB..

REFERENCES'. CITED.

TheA follwing: references are* of record. inthe' leof? this` patent:

UNITED' STATES PATENTS Number.

Name Date. Sullivan July 4, 1916 Baruch.v .Junev17, 1919 Moore, .Nov. 8, 1921v Number Number Name; Date Herz' Mar; 29,V 1932 Pettie May 16,1933 Miller Sept. 12,1933 Ceccarini .May 12, 1936 Schmidt June 16, 193.6 Owens Sept. 1-, 1936 Crosier .Oct. 6, 1939 Cail'leyv Mar. 26,1940 Howells Junelll, 1910 Gagliardi Mar. 19,1941- Huitt. Apr. 29,11- 941 Caldwell et al Feb. 17,1942

FOREIGN PATENTS Country. Date. Germany July. 6,1929 

